Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933331AbcLGWEF (ORCPT ); Wed, 7 Dec 2016 17:04:05 -0500 Received: from mail-qt0-f194.google.com ([209.85.216.194]:35983 "EHLO mail-qt0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932777AbcLGWED (ORCPT ); Wed, 7 Dec 2016 17:04:03 -0500 From: Dan Streetman To: Keith Busch , Jens Axboe Cc: Dan Streetman , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Dan Streetman Subject: [PATCH] nvme: create the correct number of queues Date: Wed, 7 Dec 2016 17:03:26 -0500 Message-Id: <20161207220326.8461-1-ddstreet@ieee.org> X-Mailer: git-send-email 2.9.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4133 Lines: 120 Change nr_io_queues variable name to nr_queues, as it includes not only the io queues but also the admin queue in its count; and change the variable name in functions that it is passed into, for clarity. Also correct misuses of the nr_queue count: In the db_bar_size() function, the calculation added 1 to the nr_io_queues value to account for the admin queue, but since that's actually already in the nr_queue count, don't add it. In the nvme_setup_io_queues() function when allocating irq vectors, it considers the minimum number of queues to be 1, but actually 2 queues are needed; 1 admin queue + at least 1 io queue. When setting the device's max_qid (maximum queue index id), it's currently set to nr_io_queues, but since nr_queues counts all queues, and because max_qid is 0-based and nr_queues is 1-based, max_qid must be set to nr_queues - 1. Signed-off-by: Dan Streetman --- drivers/nvme/host/pci.c | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index def2285..eff8198 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1007,15 +1007,15 @@ static void nvme_disable_admin_queue(struct nvme_dev *dev, bool shutdown) spin_unlock_irq(&nvmeq->q_lock); } -static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_io_queues, +static int nvme_cmb_qdepth(struct nvme_dev *dev, int nr_queues, int entry_size) { int q_depth = dev->q_depth; unsigned q_size_aligned = roundup(q_depth * entry_size, dev->ctrl.page_size); - if (q_size_aligned * nr_io_queues > dev->cmb_size) { - u64 mem_per_q = div_u64(dev->cmb_size, nr_io_queues); + if (q_size_aligned * nr_queues > dev->cmb_size) { + u64 mem_per_q = div_u64(dev->cmb_size, nr_queues); mem_per_q = round_down(mem_per_q, dev->ctrl.page_size); q_depth = div_u64(mem_per_q, entry_size); @@ -1387,27 +1387,27 @@ static inline void nvme_release_cmb(struct nvme_dev *dev) } } -static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues) +static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_queues) { - return 4096 + ((nr_io_queues + 1) * 8 * dev->db_stride); + return 4096 + (nr_queues * 8 * dev->db_stride); } static int nvme_setup_io_queues(struct nvme_dev *dev) { struct nvme_queue *adminq = dev->queues[0]; struct pci_dev *pdev = to_pci_dev(dev->dev); - int result, nr_io_queues, size; + int result, nr_queues, size; - nr_io_queues = num_online_cpus(); - result = nvme_set_queue_count(&dev->ctrl, &nr_io_queues); + nr_queues = num_online_cpus(); + result = nvme_set_queue_count(&dev->ctrl, &nr_queues); if (result < 0) return result; - if (nr_io_queues == 0) + if (nr_queues == 0) return 0; if (dev->cmb && NVME_CMB_SQS(dev->cmbsz)) { - result = nvme_cmb_qdepth(dev, nr_io_queues, + result = nvme_cmb_qdepth(dev, nr_queues, sizeof(struct nvme_command)); if (result > 0) dev->q_depth = result; @@ -1415,16 +1415,16 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) nvme_release_cmb(dev); } - size = db_bar_size(dev, nr_io_queues); + size = db_bar_size(dev, nr_queues); if (size > 8192) { iounmap(dev->bar); do { dev->bar = ioremap(pci_resource_start(pdev, 0), size); if (dev->bar) break; - if (!--nr_io_queues) + if (!--nr_queues) return -ENOMEM; - size = db_bar_size(dev, nr_io_queues); + size = db_bar_size(dev, nr_queues); } while (1); dev->dbs = dev->bar + 4096; adminq->q_db = dev->dbs; @@ -1438,11 +1438,12 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) * setting up the full range we need. */ pci_free_irq_vectors(pdev); - nr_io_queues = pci_alloc_irq_vectors(pdev, 1, nr_io_queues, + nr_queues = pci_alloc_irq_vectors(pdev, 1, nr_queues, PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY); - if (nr_io_queues <= 0) + /* we need at least 1 admin queue + 1 io queue */ + if (nr_queues < 2) return -EIO; - dev->max_qid = nr_io_queues; + dev->max_qid = nr_queues - 1; /* * Should investigate if there's a performance win from allocating -- 2.9.3